1975 K10 Transmission

[wyeaples]

So I am new in the world of old trucks and recently purchased a 1975 K10 Silverado 4x4 with the 5.7l 350. I am having some tranny issues. When it is cold, it doesnt want to shift into gear. I have to sit and rev the engine until it finally jumps into gear. I think that I have the TH350 transmission. I have been looking around the internet for brand new transmissions and rebuild kits, but that is just me shooting in the dark. Any help or suggestions would be greatly appreciated.

 

[CSFJ]

Fluid level and condition?

 

[wyeaples]

the truck is in good condition but I haven't checked the fluid level in the past week.

 

[CSFJ]

I meant condition of the fluid.

 

[wyeaples]

just checked the fluid. the condition looks great. color makes it look brand new.

 

[firebane]

Transmission is going to need a rebuild soon. Mine is doing this as well and usually means something internal is worn out.

 

[CSFJ]

Transmission is going to need a rebuild soon. Mine is doing this as well and usually means something internal is worn out.

This is probably the case here. If the fluid looks that new, the previous owner probably had issues and tried to change the fluid to help it.

 

[firebane]

This is probably the case here. If the fluid looks that new, the previous owner probably had issues and tried to change the fluid to help it.

Yup I changed fluid and new filter and nothing changed. From what I've read internal seals start to fail and it doesn't hold fluid.

Some people say you can use brake fluid mixed in to help swell the seals but its just a temporary fix.

 

[wyeaples]

Transmission is going to need a rebuild soon. Mine is doing this as well and usually means something internal is worn out.

so I'm assuming that the next step is confirming what transmission is in it. anybody have any recommended sites for ordering rebuild kits?

 

[firebane]

so I'm assuming that the next step is confirming what transmission is in it. anybody have any recommended sites for ordering rebuild kits?

Rebuilding a transmission is a job not for faint of heart. Requires a lot attention and special tools.

Look at the bottom of the pan to determine what transmission you have.

 

[wyeaples]

Rebuilding a transmission is a job not for faint of heart. Requires a lot attention and special tools.

Look at the bottom of the pan to determine what transmission you have.

I prefer to do all my work myself but I believe a transmission rebuild might be out of my skill level. This job might be taken to my mechanic.

 

[crazy4offroad]

Mine was doing something similar. I would pull out to the road, traffic coming so shift into reverse and nothing. Turns out the shifting linkage just needed a little adjustment, so I would recommend checking the basics first. If it wont go in drive pull the shifter down a little like you're trying to go to 2nd. If it kicks in gear you know what to do. If the fluid is bright red and doesn't look like it has lost any clutch material in it, it could possibly be a stuck valve in the valve body. If it turns out it really does need a rebuild, I and others posted a lot of info in this thread about where to buy parts, tips & tricks, procedures, etc....
http://www.gmsquarebody.com/forum/showthread.php?t=14404

 

[wyeaples]

I already have to adjust the shift lever toward neutral for drive to work. You mentioned a stuck valve. If we are already in the transmission for a valve fix, wouldn't it be wise to just do the whole thing?

 

[crazy4offroad]

The valve body is accessible under the pan. Rebuilding the whole trans requires removal from the truck, removing the front pump and all internals. Some tools you may have to fabricate/borrow/rent. If you already have to fiddle with the shifter I would say it has more to do with that.

 

[89Suburban]

Fort things first instead of all the speculation identify what trans you have. @yevgenievich